Device for holding drill bits



May 18, 1937.

R. A. BEDFORD DEVICE FOR HOLDING DRILL BITS Filed Sept. 19, 1955 Jmmov REGINA LD HSLINI' BEDFORD,

Patented May 18, 1937 PATENT OFFICE DEVICE FOR HOLDING DRILL BITS Reginald Asline Bedford, Stumperlowe, Sheflield, England,

Application September 19, 1935, Serial No. 41,288

In Great Britain September 26, 1934 I 4 Claims.

My invention relates to bits of the kind used in rockdrills of the percussive type and wherein the bit is provided with a socket whereby it may be removably secured to the drill shaft.

The object of the invention is to provide a device to facilitate the forging and hardening or the like of such bits whereby the said bit may be rigidly supported during the operation and easily removed when the said operation has been 1 completed.

With these and other objects in view the invention consists in a holder for rigidly supporting drill bits of the type first above referred to during the forging, hardening or like operation and comprises a tubular shank having an end suitably formed to engage the socket of the bit and an axially disposed rigid rod capable of slidable movement in the shank and of such a length that the end thereof is adapted to project beyond that end of the shank remote from the bit when the latter is in position on the shank, whereby a blow applied to the said projecting end of the axial rod. will cause the finished bit to be ejected from its seating at the end of the shank. The end of the shank adapted to engage the bit may be tapered to engage a correspondingly tapered bore of the socket of the bit. The projecting end of the axially disposed rod may be formed with a button to define an anvil surface to prevent distortion and also to retain the rod.

Referring to the drawing filed herewith:- Fig. 1 is an elevation of one form of device; Fig. 2 is a longitudinal section of Fig. 1 showing a bit held in position; and

Fig. 3 is a similar section (part only being shown) with the bit displaced ready for removal.

Fig. 4 is a plan of Fig. 1. a, is a tubular shank which has its end b 4o tapered, in order to engage the tapered socket d of a drill bit e shown only in Figs. 2 and 3. Passing longitudinally through the bore of the shank a and. slidable therein is a rigid rod 1. The length of the rod 1 is such that both ends of the rod ,1

project beyond the shank a and are formed with enlarged heads or buttons 2' and 9', respectively, serving to retain the rod slidably in the shank within the limits of the distance apart of the two buttons 2' and j.

A collar is is sweated on the shank a, the collar having resilient claws or fingers m for tightly gripping the inner end of the bit e when seated in position, as shown in Fig. 2. These fingers effectively hold the bit from dropping off and the bit is easily removed by unseating it as shown in Fig. 3 by a blow upon the button :i to cause the rodf'toproject at the end I) of the shank thereby displacing the drill bit from its seating so that it can be removed.

The button 7' may be omitted where desired to enable the rod to be withdrawn from the shank a at any time.

When the holder is used for hardening bits by plunging them into a hardening liquid it may be desirable to provide means for permitting the escape of fumes from between the co-operating surfaces of the bit and the holder and this may be accomplished by providing a longitudinal passage n in the end of the rod adjacent the bit 6, the said passage having a lateral branch passage 15 0 communicating with the clearance space between the rod 1 and the wall of the bore of the shank a so that the fumes can pass through the said space and out through a hole p provided at any suitable point in the shank for the purpose.

The shank a intermediate of its ends may be of round, square, octagonal or other suitable cross section.

What I claim and desire to secure by Letters Patent is:-

l. A device for holding socketed drill bits during hardening, forging or like operations comprising a tubular shank, a tapered end to said shank for fitting interiorly the tapered socket of the bit, a collar upon said shank having spaced 30 fingers circumferentially around said end in spaced relation thereto for accommodating the wall of said socket so as to frictionally retain the hit upon the shank, an axially slidable rigid rod disposed interiorly of the tubular shank and pro- 35 jecting through said tapered end thereof and adapted to contact with the inner end of the socket for dislodging the bit from the shank, and means in the rod and shank for permitting the escape of fumes from co-operating surfaces 40 of the socket of the bit and the rod.

2. A device for holding socketed drill bits during hardening, forging or like operations comprising a tubular shank, a tapered end to said shank for fitting interiorly the tapered socket of 45 the bit, a collar upon said shank having spaced fingers circumferentially around said end in spaced relation thereto for accommodating the wall of said socket so as to frictionally retain the hit upon the shank, an axially slidable rigid rod 5 disposed interiorly of the tubular shank and projecting through said tapered end thereof and adapted to contact with the inner end of the socket for dislodging the bit from the shank, means on said rod for retaining it within said 55 shank, and means in the rod and shank for permitting the escape of fumes from co-operating surfaces of the socket of the bit and the rod.

3. A device for holding socketed drill bits during hardening, forging or like operations comprising a tubular shank, a tapered end to said shank for fitting interiorly the tapered socket of the bit, a collar upon said shank having spaced fingers oircumferentially around said end in spaced relation thereto for accommodating the wall of said socket so as to frictionally retain the bit upon the shank, an axially slidable rigid rod in the tubular shank and projecting therefrom at both ends and adapted to contact with the inner end of the socket for dislodging the bit from the shank, said projecting ends of said rod being provided with heads for retaining said rod in said shank, and means in the rod and shank for permitting the escape of fumes from the co-operating surfaces of the socket of the bit and the rod.

4. A device for holding socket drill bits during hardening, forging or like operations comprising a tubular shank, a tapered end to said shank for fitting interiorly the tapered socket of the bit, a collar upon said shank having spaced fingers circumferentially around said end in spaced relation thereto for accommodating the wall of said socket so as to frictionally retain the bit upon the shank, an axially slidable rigid rod in the tubular shank and projecting therefrom at both ends and adapted to contact with the inner end of the socket for dislodging the bit from the shank, said projecting ends of said rod being provided with heads for retaining said rod in said shank, and means in the rod and shank for permitting the escape of fumes from the cooperating surfaces of the bit and the rod, said means comprising a fume conveying duct in said rod communicating from the socket "of the bit to the interior of the shank and a fume outlet duct in said shank and means on the rod for retaining it within the shank.

REGINALD ASLINE BEDFORD. 

